1. Field of the Invention
The present invention relates to cargo security systems, and more particularly to a security system for the protection of cargo located in a truck or similar vehicle during transport in which a digital counter display device is mounted on the exterior truck cargo door or cargo door lock enclosure and displays a number which changes upon opening of the cargo door or lock to indicate that the vehicle cargo area may have been accessed during transit.
2. Description of Prior Art including Information Disclosed Under 37 CFR 1.97 and 1.98
Currently, it is very common for trucks used to transport cargo to utilize a plastic or metal seal attached to the J-hook of the lock of a truck door. The physical seal is attached to the lock by the shipper after the truck is loaded with cargo and the door has been locked, before the truck leaves the shipper to travel to its destination.
In order to open the truck door and access the cargo, it is necessary to break the seal. Hence, the physical seal acts as a visual indicator as to whether the vehicle door has been opened during transit. At the destination, the recipient observes the physical seal when the truck arrives, before the vehicle door is opened. If the seal remains intact, the recipient knows that the vehicle door has not been opened and thus the cargo has not been tampered with during transit. If the seal is broken, the recipient knows that the vehicle door has been opened permitting access to the cargo and thus not to accept the shipment.
However, the physical seal has disadvantages. The seal may be damaged or broken for reasons other than accessing the cargo, causing the shipper to refuse the shipment even though the cargo has not been tampered. Further, it is difficult for the shipper to lock the vehicle door and at the same time place a seal on the lock because the seal must be attached to the J-hook of the lock, the part that is received in the door jam to secure the door.